//一段时间没启动，，，配置又出问题，只能运行不能调试。。。
#include <stdio.h>
char* strcat_1(char* str1,const char* str2)
{
    char* tmp = str1;
    while (*tmp != '\0')
    {
        tmp++;
    }
    while (*str2 != '\0') 
    {
        *tmp = *str2;
        str2++;
        tmp++;
    }
    *tmp = '\0';
    return tmp;
}

char* strcat_2(char str1[], const char str2[])
{
    char* tmp = str1;
    while (*tmp != '\0')
    {
        tmp++;
    }
    while (*str2 != '\0')
    {
        *tmp = *str2;
        str2++;
        tmp++;
    }
    *tmp = '\0';
    return tmp;
}

int main()
{
    char str1[15] = "hello,";
    char str2[10] = "world.";
    strcat_2(str1, str2);
    printf("%s", str1);
    return 0;
}